We plan to study some aspects of the control of renin synthesis, the location of the receptor sites for angiotensin in brain, the possible permissive effect of angiotensin for renal action of ADH and finally some aspects of the nature of renal hypertrophy. In vitro incorporation of C14 leucine into renin in dog kidney slices can be studied using techniques developed in our laboratory. Rates of incorporation will be measured in a large variety of conditions. Brain uptake of labelled angiotensin will be measured after intravenous infusion or ventricular-cysternal infusion. The role of angiotensin in the antidiuretic response to ADH will be studied in alcohol anesthetized water loaded rats. The response to test doses of ADH will be determined in rats on high and low salt diets and in rats before and after infusion of the angiotensin blocker 1-sacrosine-8-alanine angiotensin. Finally, some of the physiological and biochemical responses to unilateral nephrectomy will be studied in rats.